This invention relates generally to coating bond pads in the fabrication of integrated circuits.
It is generally desirable to coat wire bond pads and solder ball bond pads with nickel and gold. Currently these coating processes are implemented simultaneously on both types of bond pads. Wire bond bond pads typically need more gold than solder ball bond pads. Too little gold causes wire bonding problems. Too much gold causes solder ball joint embrittlement.
As a result, in situations in which both types of bond pads are contained on the same structure, conventional processing provides either too much gold to suit the solder ball bond pads or to˜ little gold to suit the wire bond pads. Certainly, providing excessive gold coatings is generally not cost effective.
Thus, there is a need for a better way to coat bond pads in fabricating structures with both solder ball and wire bond bond pads.